Like many Modernist novels, La Nausée is a "city-novel", encapsulating experience within the city. It is widely assumed that Bouville in the novel is a fictional portrayal of Le Havre, where Sartre was living and teaching in the 1930s as he wrote it.
The critic William V. Spanos has used Sartre's novel as an example of "negative capability", a presentation of the uncertainty and dread of human existence so strong that the imagination cannot comprehend it.
The Cambridge Companion to the French Novel places La Nausée in a tradition of French activism: "Following on from Malraux, Sartre, Beauvoir, and Camus among others were all able to use the writing of novels as a powerful tool of ideological exploration." Although novelists like Sartre claim to be in rebellion against the 19th Century French novel, "they in fact owe a great deal both to its promotion of the lowly and to its ambiguous or 'poetic' aspects."
In his essay What Is Literature?, Sartre wrote, "On the one hand, the literary object has no substance but the reader's subjectivity ... But, on the other hand, the words are there like traps to arouse our feelings and to reflect them towards us ... Thus, the writer appeals to the reader's freedom to collaborate in the production of the work."
The novel, according to Sartre, is an intricate formal achievement modeled on much 18th-century fiction that was presented as a "diary discovered among the papers of...".
Hayden Carruth wonders if there are unrecognized layers of irony and humor beneath the seriousness of Nausea: "Sartre, for all his anguished disgust, can play the clown as well, and has done so often enough: a sort of fool at the metaphysical court."
Like many modernist authors, Sartre, when young, loved popular novels in preference to the classics and claimed in his autobiography that it was from them, rather than from the balanced phrases of Chateaubriand, that he had his "first encounters with beauty".
Sartre described the stream of consciousness technique as one method of moving the novel from the era of Newtonian physics forward into the era of Einstein's theory of general relativity, in terms of writing style. He saw this as crucial because he felt that "narrative technique ultimately takes us back to the metaphysics of the novelist." He wanted his novelistic techniques to be compatible with his theories on the existential freedom of the individual as well as his phenomenological analyses of the unstable, shifting structures of consciousness.